This specification recites a number or prior art documents. The disclosure content of said documents is herewith incorporated by reference.
The present invention relates to the use of etherlysophospholipids (ELPs) for the preparation of a medicament for the prevention or treatment of an inflammatory disease without causing or essentially without causing adverse gastrointestinal side effects and/or without inhibition of phospholipase A2 and prostaglandin E2, as well as for preventing or treating ulcerative conditions of the gastrointestinal tract.
The inflammatory response is an essential mechanism of defense of the organism against the attack of infectious agents, and it is also implicated in the pathogenesis of many acute and chronic diseases, including autoimmune disorders. In spite of being needed to fight pathogens, the effects of an inflammatory burst can be devastating. It is therefore often necessary to restrict the symptomatology of inflammation with the use of anti-inflammatory drugs.
Inflammation is a complex process normally triggered by tissue injury that includes activation of a large array of enzymes, the increase in vascular permeability and extravasation of blood fluids, cell migration and release of chemical mediators, all aimed to both destroy and repair the injured tissue.
Inflammation is commonly treated with so-called non-steroid anti-inflammatory drugs (NSAIDs). Although chemically diverse, all NSAIDs act by inhibiting cyclooxygenase (COX) activity, thus resulting in suppression of the production of inflammatory prostaglandins (PG). Two cyclooxygenase enzymes, named COX-1 and COX-2, have been described, which catalyze the synthesis of prostaglandins from arachidonic acid [Xie et al., Proc. Natl. Acad. Sci., 88, 2692 (1991)]. COX-1 is expressed in most tissues and is responsible for the synthesis of. PGs needed to maintain gut and kidney integrity, whereas COX-2 is induced at sites of tissue damage, where it leads to the synthesis of inflammatory PGs and other inflammatory mediators [Kargman et al., Gastroenterology, 111, 445 (1996)].
While protecting from inflammatory damage, all NSAIDs tested so far have important gastrointestinal toxic side effects, mostly due to the inhibition of the synthesis of cytoprotective prostaglandins (mainly PGE2). Therefore, anti-inflammatory NSAIDs that act selectively on COX-2, and not on COX-1, have been eagerly searched for and developed. However, COX-2 inhibitors turned out to inhibit inflammation only at concentrations that also inhibited COX-1, and hence provoke mucosal toxicity through suppression of gastric PGE2 synthesis [Wallace et al., Gastroenterology, 115, 101 (1998)]. Indeed NSAIDs inhibit ulcer healing by interfering with the synthesis of growth factors involved in repair of the gastric mucosa. For example, it has been shown that indomethacin, a potent NSAID, inhibits the production of PGs and of Hepatocyte Growth Factor (HGF), a mediator of epithelial growth and angiogenesis at the site of ulcerative mucosal erosion [Bamba et al., Biochem. Biophys. Res. Comm., 245, 567 (1998)].
Furthermore, the finding that gene-targeted, COX-2 deficient mice are still able to mount a normal inflammatory response, but suffer from kidney dysfunction [Morham et at., Cell, 83, 473 (1995)] has additionally challenged the selective inhibition of COX-2.
Finally, as a result of the inhibition of PG synthesis, the accumulative increase in arachidonic acid enhances the production of leukotrienes by the lipooxygenase enzyme, thus resulting in vasoconstriction, a life-threatening side effect in individuals with asthmatic or circulatory complications [Fosslien E., Annals Clin. and Lab. Science, 28, 67 (1998)].
A further group of NSAIDs named etherlysophospholipids (ELPs) or alkyl-lysophospholipids (ALPs) are known for their antineoplastic properties (DE 2,619,686), in particular ET-18-OCH3 (also known as edelfosine) having the formula: 
Edelfosine, one of the best studied ELPs, has been shown to induce cell death by apoptosis selectively on tumor cells, while sparing normal, non-transformed cells [Mollinedo et al., Cancer Res., 57, 1320 (1997)]. Edelfosine and several other ether lipid compounds have undergone phase I/II clinical evaluation for the treatment of cancer or their use as purging agents in autologous bone marrow transplantation [Lohmeyer et al., Drugs of the Future, 19, 1021 (1994)].
Moreover, U.S. Pat. No. 5,266,564 discloses the use of a series of ELPs, including several compounds used in accordance with the present invention, in the treatment of autoimmune diseases, such as rheumatoid arthritis and ankylosing spondylitis.
EP 236,390 B discloses the use of such compounds in the treatment of multiple sclerosis, another autoimmune illness.
From DE 3,941,009 the effectiveness of edelfosine to eliminate activated lymphocytes is known.
Recently, Bosse et al. [Pathobiology, 63, 109 (1995)] have described the selective inhibition of adhesion molecule expression in vitro by edelfosine on endothelial cells. Potential anti-inflammatory properties of edelfosine have been mentioned from such capacity of inhibition, but according to the cited article, the in vivo anti-inflammatory activity of edelfosine was not tested in animal models. As is well known in the art, the pharmaceutical in vivo activity of a compound including the potential occurrence of adverse side effects cannot be predicted from in vitro data without further ado.
Thus, no NSAID is available to date that combines potent in vivo anti-inflammatory properties with the lack or a minimum of toxic side effects on the gastrointestinal mucosa [Cryer et al., Am. J. Med., 104, 413 (1998)]. Accordingly, there is a need in the art to develop effective anti-inflammatory agents that are free of or essentially free of toxic gastrointestinal side effects for in vivo therapy in mammals, preferably humans.
The solution to this technical problem is achieved by providing the embodiments characterized in the claims.
Accordingly, the present invention relates to the use of a compound of formula (I): 
wherein R1 is a C12-C18 straight or branched alkyl group;
R2 is C1-C8 straight or branched alkyl group;
and R3 is: 
or the salts, enantiomers and diastereomers thereof, for the preparation of a pharmaceutical composition for the prevention or treatment of an inflammatory disease.
Unexpectedly, it has now been found that the above recited compounds are useful in the treatment of an inflammatory disease in mammals and do not inhibit the synthesis of prostaglandins, in particular prostaglandin E2. It was surprisingly and additionally found that synthesis of phospholipase A is not inhibited. Most advantageously, they do not cause or they essentially do not cause adverse gastrointestinal side effects, thereby obviating the disadvantages associated with the use of traditional NSAIDs. Furthermore, surprisingly it has now been found that the recited compounds are useful in the prevention or treatment of ulcerative conditions of the gastrointestinal tract in mammals. The mammals to which these pharmaceutical compositions are preferably administered are humans. The term xe2x80x9cessentially not causing adverse side effectsxe2x80x9d means, in accordance with the present invention, that the overall well-being of the subject treated is not impaired as a consequence of the administration of the pharmaceutical composition of the invention.
The compounds of formula (I) have one or more asymmetric centres and thus they can exist as enantiomers or diastereomers. The pharmaceutical composition prepared in accordance with the present invention may include both mixtures of and separate individual isomers.
The compounds of formula (I) can be obtained in the form of salts of formulas (Ia) or (Ib) 
wherein Xxe2x88x92 is a pharmaceutically acceptable anion, such as chloride, bromide or iodide, and R1 and R2 have the above mentioned meanings, or of formulas (Ic) or (Id) 
wherein M+ is an alkali metal cation (e.g. Na+, K+) or represents a half amount of an alkaline-earth metal cation (e.g. xc2xd Ca2+, xc2xd Mg2+), and R1 and R2 have the above mentioned meanings.
In a preferred embodiment of the use of the invention the compounds of formula (I) are those wherein R1 is C16-C18 straight alkyl group and R2 is methyl.
In a particularly preferred embodiment of the use of the invention the compound is the compound of formula: 
In another particularly preferred embodiment of the use of the invention, the compound is the compound of formula: 
In another preferred embodiment of the use of the invention said inflammatory disease is a chronic inflammatory disease.
In a further preferred embodiment of the use of the present invention, said inflammatory disease is associated with an ulcerative condition of the gastrointestinal tract.
In a particularly preferred embodiment of the use of the invention said chronic inflammatory disease is associated with inflammatory bowel diseases, particularly ulcerative colitis or Crohn""s disease.
In another particularly preferred embodiment of the use of the invention said chronic inflammatory disease is associated with inflammatory diseases of the respiratory ways, like asbestosis or silicosis, inflammatory processes derived from alcoholic liver, like liver cirrhosis, and other inflammatory diseases, like pemphigus vulgaris, polymyositis-dermatomyositis, Sjogren-syndrome, Lyme disease, lupus erythematosus or Behget""s disease.
In another further preferred embodiment of the use of the invention said inflammatory disease is an acute inflammatory disease, particularly associated with infective diseases, non-rheumatic inflammation, like bursitis, synovitis, capsulitis, tendinitis and/or other inflammatory lesions of traumatic and/or sportive origin.
The present invention further relates to a method of preparing a medicament effective in the prevention or treatment of an inflammatory disease without causing or essentially without causing adverse gastrointestinal side effects comprising the step of formulating a compound of formula (I) into a pharmaceutically acceptable carrier.
The preparation of the compounds of formula (I) according to the present invention can be performed in one of the ways which have been described in the literature, for example, Berchtold R., Chem. Phys. Lipids, 30, 389 (1982); Woolley P. and Eibl H., Chem. Phys. Lipids, 47, 55 (1988); and Eibl H., Chem. Phys. Lipids, 26, 405 (1980).
The invention furthermore relates to a method for the prevention or treatment of an inflammatory trait comprising administering an effective amount of formula (I): 
Wherein R1 is a C12-C18 straight or branched alkyl group;
R2 is C1-C8 straight or branched alkyl group;
and R3 is: 
or the salts, enantiomers and diastereomers thereof, to a patient in need thereof.
In a preferred embodiment of the method of the present invention R1 is a C16-C18 straight alkyl group and R2 is methyl.
In a particularly preferred embodiment of the method of the present invention the compound of formula (I) is: 
In another particularly preferred embodiment of the method of the present invention the compound of formula (I) is: 
In another preferred embodiment of the method of the present invention said inflammatory disease is a chronic inflammatory disease.
In a further preferred embodiment of the method of the present invention said inflammatory disease is associated with an ulcerative condition of the gastrointestinal tract.
In a particularly preferred embodiment of the method of the present invention said chronic inflammatory disease or said ulcerative condition is associated with an inflammatory bowel disease.
In a further particularly preferred embodiment of the method of the present invention said inflammatory bowel disease is ulcerative colitis, Crohn""s disease, a gastric ulcer or a duodenal ulcer.
In another particularly preferred embodiment of the method of the present invention said chronic inflammatory disease is associated with inflammatory diseases of the respiratory ways like asbestosis or silicosis.
In an additional particularly preferred embodiment of the method of the present invention said chronic inflammatory disease is associated with inflammatory processes derived from alcoholic liver, like liver cirrhosis.
In a further particularly preferred embodiment of the method of the present invention said chronic inflammatory disease is associated with other inflammatory diseases, like pemphigus vulgaris, polymyositis-dermatomyositis, Sjxc3x6gren-syndrome, Lyme disease, lupus erythematosus or Behget""s disease.
The invention in another preferred embodiment relates to a method wherein said inflammatory disease is an acute inflammatory disease.
In a particularly preferred embodiment of the method of the present invention said acute inflammatory disease is associated with infective diseases, non-rheumatic inflammation, like bursitis, synovitis, capsulitis, tendinitis and/or other inflammatory lesions of traumatic and/or sportive origin.
For the intended therapeutic uses, the compounds of the invention are formulated in suitable pharmaceutical compositions, which may further comprise a pharmaceutically acceptable carrier and/or diluent. Examples of suitable pharmaceutical carriers are well known in the art and include phosphate buffered saline solutions, water, emulsions, such a oil/water emulsions, various types of wetting agents, sterile solutions etc. Compositions comprising such carriers can be formulated by well-known conventional methods. These pharmaceutical compositions can be administered to the subject at a suitable dose. Administration of the suitable compositions may be effected by different ways, e.g., by oral, intravenous, intraperitoneal, subcutaneous, intramuscular, topical, intradermal, intranasal or intrabronchial administration. The attending physician and clinical factors will determine the dosage regimen. As it is well known, pharmaceutical dosages for any one patient depend upon many factors, including the patient size, body surface area, age, the particular compound to be administered, sex, time and route of administration, general health, and others drugs being administered concurrently. A typical dose can be, for example, in the range of 1 to 100 mg, preferably 10 to 50 mg; however, doses below or above these ranges are envisioned, especially considering the aforementioned factors. Generally, the regimen as a regular administration of the pharmaceutical composition should be in the range of 1 to 100 mg units, preferably 10 to 50 mg units per day. If the regimen is a continuous infusion, it should also be in the range of 1 xcexcg to 10 mg units per kilogram of body weight per minute, respectively. Progress can be monitored by periodic assessment. The compositions of the invention may be administrated locally or systemically. Administration will be generally oral or parenteral. Preparations for oral or parenteral administration include pharmaceutical solid forms, aqueous or non-aqueous solutions, suspensions, and emulsions. Examples of solids forms include pellets, tablets, pills, powders, capsules, and any other galenic solid form. Examples of non-aqueous solvents are propylene glycol, polyethylene glycol, vegetable oils such a olive oil, and injectable organic esters such a ethyl oleate. Aqueous carriers include water, alcoholic/aqueous solutions, emulsions or suspensions, including saline and buffered media. Parenteral vehicles include sodium chloride solution, Ringer""s dextrose and sodium chloride, lactated Ringer""s, or fixed oils. Intravenous vehicles fluid and nutrient replenishers, electrolyte replenishers (such as those based on Ringer""s dextrose), and the like. Preservatives and other additives may also be present such as, for example, antimicrobials, anti-oxidants, chelating agents, and inert gases and the like.
In accordance with the present invention it was found that the use of the compounds of the invention presents the following advantages: (i) the anti-inflammatory potential of the compounds of the invention in vivo in an animal model is superior to that of currently used potent NSAIDs; (ii) xe2x80x9cin vitroxe2x80x9d experiments indicate that the compounds of the invention down-regulate the cell surface expression of adhesion molecules (CD43, CD44 and L-selectin-CD62L-) in human peripheral blood neutrophils; (iii) the anti-inflammatory properties of the compounds of the invention are not related to their tumoricidal properties, as non-cytotoxic ELPs retain full anti-inflammatory capacity; (iv) surprisingly and unexpectedly, the compounds of the invention exert their anti-inflammatory function without affecting the production of PGE2 and the activity and expression of COX-1 and COX-2, and hence are free of the gastrointestinal ulceration side effects of the known NSAIDs. Furthermore, the compounds of the invention do not affect expression of cytosolic PLA2 and are able to increase PLA2 activity; and (V) surprisingly the compounds used in accordance with the invention prevent or treat ulcerative conditions of the gastrointestinal tract.
Furthermore, in accordance with the present invention, it was demonstrated that: (i) the potent anti-inflammatory potential of the compounds used in accordance with the invention in an animal model is superior to the action of indomethacin, one of the most potent NSAID; (ii) at the cellular level, the anti-inflammatory potential was shown to relate to the capacity of the compounds used in accordance with the invention to decrease the expression of adhesion cell surface molecules and to inhibit the formation of free radicals in leukocytes. The L-selectin down-regulation effect of said compounds was higher than that induced by the phorbol ester PMA; (iii) surprisingly, it was also found that the unexpectedly high anti-inflammatory properties of said compounds are not related to the inhibition of the synthesis of the inflammatory prostaglandin PGE2, whereas indomethacin, used as a control, abolishes completely the PGE2 production. Furthermore, the compounds of the invention stimulated PLA2 activity, as measured by [3H]arachidonic acid release. Hence, said compounds fulfill both the requirements of having strong anti-inflammatory potential without affecting the production of gastric mucosa protective prostaglandin; (iv) surprisingly, it was found that said compounds present a good therapeutic potential in an animal model of ulcerative colitis.
It is important to note that the anti-inflammatory treatment with the compounds used in this invention is free of gastrointestinal ulceration side effects. This is due to the lack of inhibition of enzymatic activity of the COX-1 and COX-2 enzymes by the compounds used in this invention which prevents depletion of gastroprotective PGE2 during the anti-inflammatory treatment. Thus, the compound is perfectly applicable for administration in mammals, preferably humans. It is also important to note that the compounds used in the present invention can be used to treat ulcerative conditions of the gastrointestinal tract.
In the examples and figures described below, IEC01 means ET-18-OCH3 or Edelfosine, wherein R1 is a C18 straight alkyl group, R2 is a methyl group and R3 is xe2x80x94(CH2)2xe2x80x94N+(CH3)3 and IES01 is a compound of formula (I) wherein R1 is a C16 straight alkyl group, R2 is a methyl group and R3 is xe2x80x94CH2xe2x80x94CH(COOH)xe2x80x94N+H3.